An electromagnetic coupling device includes an electromagnetic coil, a field core including a recessed portion containing the electromagnetic coil, and a terminal block inserted in a hole passing through the wall of the recessed portion. The terminal block includes a terminal portion projecting outside the field core, a pair of terminals provided at the terminal portion, and a pair of through holes passing through the terminal block via the pair of terminals. The winding start end and winding termination end of the electromagnetic coil pass through the pair of through holes, project from the pair of terminals, and are soldered to the pair of terminals together with a pair of external connection lead wires.

A clutch assembly includes a clutch mechanism and an energy harvesting device. The clutch mechanism includes an input member, an output member, and an actuating mechanism to govern selective torque transmission from the input member to the output member. The actuating mechanism is powered by electrical current. The energy harvesting device is electrically connected to the actuating mechanism, and the energy harvesting device is configured to scavenge available energy to generate the electrical current that powers the actuating mechanism.

A seal structure for an electromagnet lead wire includes an annular yoke including an annular groove, a wiring hole configured to pass a lead wire of an exciting coil, an insulating resin configured to seal the exciting coil, and a seal member arranged in the hole. The wiring hole includes a though hole of a case, and a concave portion of the yoke. The insulating resin includes a projecting portion whose distal end face is located in the concave portion. The seal member includes a columnar portion inserted into the though hole, and a flange portion located in the concave portion. The flange portion is sandwiched and compressed between the device inner surface of the case and the distal end face of the insulating resin.

An electromagnetic coupling device includes an electromagnetic coil, a field core including a recessed portion containing the electromagnetic coil, and a terminal block inserted in a hole passing through the wall of the recessed portion. The terminal block includes a terminal portion projecting outside the field core, a pair of terminals provided at the terminal portion, and a pair of through holes passing through the terminal block via the pair of terminals. The winding start end and winding termination end of the electromagnetic coil pass through the pair of through holes, project from the pair of terminals, and are soldered to the pair of terminals together with a pair of external connection lead wires.

A field core unit for an electromagnetic clutch can include: a field coil generating a magnetic flux; a magnetic part provided with an annular-shaped insertion groove encompassing lower and side portions of the field coil such that the magnetic flux flows through the magnetic part; and a field core configured such that an upper surface thereof is open and an interior space is formed therein. The magnetic part can be inserted into the field core.

A monostable electromagnetic clutch is provided having a movable assembly and an electromagnetic assembly. The movable assembly is provided thereon with a return springs and can pass through the electromagnetic assembly. The electromagnetic assembly generates electromagnetic force when it is energized, and under a driving action of the electromagnetic force and an spring force of the return springs, the movable assembly can reciprocate in the electromagnetic assembly.

A clutch and a compressor including the same, and may include a hub fastened to a rotary shaft of a compressor and rotatable with the rotary shaft in a state where its position has been fixed, a disk fastened to the hub and rotatable with the hub, a pulley rotated by receiving power from a driving source of the compressor, an elastic member fastening the hub and the disk, fastening the hub and the disk so that the disk approaches or is away from the pulley based on the hub, a field coil assembly magnetized when power is applied to contact or space the disk and the pulley, an attenuation member interposed between the elastic member and the disk, thereby reducing the noise and vibration due to the contact and spacing between the disk and the pulley by the elastic member and the attenuation member.

An example electromagnetic clutch assembly includes a rotatable portion and a stationary portion. The rotatable portion includes a field winding and a clutch body, and the stationary portion includes an exciter winding that is inductively coupled to the rotatable portion and is operable to energize the field winding. The field winding is operable, when energized, to provide a magnetic field that causes engagement or disengagement between the clutch body and an armature body. A method of operating an electromagnetic clutch assembly is also disclosed.

A clutch assembly includes a clutch mechanism and an energy harvesting device. The clutch mechanism includes an input member, an output member, and an actuating mechanism to govern selective torque transmission from the input member to the output member. The actuating mechanism is powered by electrical current. The energy harvesting device is electrically connected to the actuating mechanism, and the energy harvesting device is configured to scavenge available energy to generate the electrical current that powers the actuating mechanism.

An example electromagnetic actuator includes a drive shaft, a motor operable to rotate the drive shaft, and a load shaft coupled to an armature body. A clutch is operable to control whether the drive shaft engages the load shaft. A rotatable portion of the clutch corotates with the drive shaft and includes a field winding and a clutch body. A stationary portion of the clutch includes an exciter winding that is inductively coupled to the rotatable portion and is operable to energize the field winding. The field winding is operable, when energized, to provide a magnetic field that causes engagement or disengagement between the clutch body and an armature body. A method of operating an electromagnetic actuator is also disclosed.